A. Field of the Invention
The present invention relates to manipulator apparatus and more particularly to manipulator apparatus including an improved control system wherein a supervisor programs a supervisory control unit of the overall control system in a first teaching phase independent of location and operation of the manipulator apparatus to define and store control parameters representing movement of the manipulator arm independent of work path distance and orientation. An operator/programmer personnel during a second teach phase programs the manipulator apparatus by the recording of positional signals representing the predetermined work paths; the control parameters stored in the supervisory control unit during the initial programming phase being recorded into a main control memory along with the positional work path signals in sequential correspondence. The recorded control parameters and positional signals are read out during a playback cycle as command signals to control movement of the manipulator apparatus along the work paths and to describe movement about the work paths represented by the control parameters stored during the teaching phase.
B. Description of the Prior Art
Programmed manipulator apparatus utilizing various programming techniques have been developed for work operation such as welding, assembling and repetitive work cycles.
One type of programmed manipulator apparatus disclosed in co-pending application Ser. No. 696,903 filed on June 17, 1976 by T. H. Lindbom, now U.S. Pat. No. 4,115,684, provides a lightweight, portable manipulator apparatus which can be readily moved to a given area, clamped in position, programmed by manually moving the end of the manipulator arm over a desired welding path in that area and operated in a playback cycle to automatically perform welding tasks over the work paths. Encoders associated with each axis of the manipulator produce data signals representing movement of the arm in each of the axes as an operator moves the arm over the desired work path. A teach head carried on the end of the arm develops control pulses for each predetermined increment of movement of the arm along the work path; the control pulses being utilized to effect recording of the encoder signals. The recorded signals are then utilized as command signals during playback to move the manipulator apparatus over the programmed path.
Another manipulator arrangement disclosed in U.S. Pat. No. 4,030,617 which issued to A. Richter on June 21, 1977 utilizes a teaching arrangement carried on the head of the manipulator.
A manipulator including an arrangement for aligning randomly oriented parts is disclosed in U.S. Pat. No. 3,885,295 which issued to J. F. Engelberger et al on May 27, 1975. The aligning arrangement moves one of the parts over a predetermined pattern after the part is first moved to a predetermined assembly position.
While the programmed manipulator apparatus of the prior art have in general been satisfactory for their intended purpose, they do not facilitate the recording by supervisory personnel of control parameters such as weld speed, weld conditions, and weaving patterns representative of manipulator arm movement about the taught work paths. Further, it would be desirable to facilitate the programming of such control parameters at a location independent of the work area and at a time prior to the teaching phase by supervisory personnel for each work path in a sequence of work paths defined in a work cycle.